JP2014007020A - Light-emitting panel and light-emitting panel manufacturing method - Google Patents

Abstract

A light-emitting panel having a structure capable of sharing a manufacturing method excellent in mass productivity in a manufacturing process is realized.
The light emitting panel includes a light emitting portion that emits light and a light transmitting portion that transmits external light. The transmissive light emitting region 10 includes a light emitting part that emits light and a light transmissive part that transmits light. The light emitting unit includes a light emitting unit that emits light, and a conductive reflective layer 13 that blocks and reflects light. The light emitting portion includes a conductive and translucent first electrode layer 12 electrically connected to one surface of the reflective layer 13, and a conductive and translucent second electrode disposed opposite to the first electrode layer 12. An electrode layer 15 and an organic EL layer 14 interposed between the second electrode layer 15 and the first electrode layer 12 are included. The light transmission part includes the first electrode layer 12, the second electrode layer 15, and the organic EL layer 14 where the reflective layer 13 is not located. A space between the first electrode layer 12 and the organic EL layer 14 of the light transmitting portion 10a is filled with a resin layer (insulating light transmitting layer) 18.
[Selection] Figure 7

Description

  Embodiments described herein relate generally to a light emitting panel and a light emitting panel manufacturing method.

  A light emitting panel in which a plurality of light emitting units and a plurality of light transmitting units of an organic EL (Electro-Luminescence) element are configured is known. This light-emitting panel can be seen through when the light-emitting unit is not lit, and can be used for illumination when the light-emitting unit is lit. As a result, it is known to use a lighted window at daytime and a lighting device at night.

  In such a light emitting panel, the light transmitting portion around the light emitting portion is a space. Because of this space, there is a problem that the upper transparent electrode cannot take the same film forming method as the spin coating method used to form the lower transparent electrode. In addition, it is necessary to partially form the light-emitting portion. In this respect, when a different manufacturing method is used, there is a problem that the manufacturing complexity is increased and the mass productivity is impaired.

JP 2011-249541 A

  In this embodiment, it is providing the light emitting panel of the structure which can use the manufacturing method excellent in mass-productivity, and this light emitting panel manufacturing method.

  The light-emitting panel according to the embodiment is a light-emitting panel that includes a transmissive light-emitting region that emits light and transmits light, and the transmissive light-emitting region includes a light emitting unit that emits light, and a light transmissive unit that transmits light. The light emitting unit includes a light emitting unit that emits light, and a conductive reflective layer that blocks and reflects light, and the light emitting unit is electrically connected to one surface of the reflective layer. A conductive and translucent first electrode layer connected to the first electrode layer; a conductive and translucent second electrode layer disposed opposite to the first electrode layer; the second electrode layer and the first electrode; An organic EL layer interposed between the first electrode layer, the second electrode layer, and the organic EL layer. And a resin layer filled in a space between the first electrode layer and the organic EL layer of the light transmission portion.

  In addition, the light emitting panel manufacturing method of the embodiment is a method for manufacturing a light emitting panel having a transmissive light emitting region that emits light and transmits light, and is light-transmitting on the surface of a non-moisture transmissive substrate. A conductive first electrode layer is formed, a conductive reflective layer is formed on the first electrode layer, an organic EL layer is formed on the reflective layer, and light is transmitted on the organic EL layer. A conductive and conductive second electrode layer is formed, and a resin layer is formed by filling a resin between the first electrode layer and the organic EL layer other than the position of the reflective layer. A film was formed by spin coating, and a necessary portion was formed by photolithography using a mask.

It is a conceptual diagram which shows the planar structure of the light emission panel used by this embodiment. It is a schematic diagram showing an example of the Ia-Ib line cross section of FIG. It is a schematic diagram showing another example of the cross section of the Ia-Ib line of FIG. It is a conceptual diagram which shows the plane structure for demonstrating 1st Embodiment regarding a light emission panel. It is the IIa-IIb sectional view taken on the line of FIG. It is the IIc-IId sectional view taken on the line of FIG. It is the IIe-IIf sectional view taken on the line of FIG. It is sectional drawing which expands and shows a part of FIG. It is a conceptual diagram which shows the plane structure for describing 2nd Embodiment regarding a light emission panel. It is sectional drawing which expands and shows a part of FIG. It is a conceptual diagram which shows the plane structure for demonstrating 3rd Embodiment regarding a light emission panel. It is sectional drawing which expands and shows a part of FIG.

  Hereinafter, embodiments will be described in detail with reference to the drawings. In the drawings described below, components having the same function are denoted by the same reference numerals, and the description thereof will not be repeated.

  The principle of the light-emitting panel used in this embodiment will be described with reference to FIGS. FIG. 1 is a conceptual diagram showing a planar configuration. FIG. 2 is a schematic diagram illustrating an example of a cross section taken along line Ia-Ib in FIG. 1, and FIG. 3 is a schematic diagram illustrating another example of a cross section taken along line Ia-Ib in FIG.

  A planar light emitting panel 100 illustrated in FIG. 1 includes a transmissive light emitting region 10 and a peripheral region 20 provided around the transmissive light emitting region 10. As will be described later in detail, the transmissive light emitting region 10 emits light and allows light to pass between the first main surface 100A and the second main surface 100B.

  As shown in FIG. 2, the first main surface 100 </ b> A and the second main surface 100 </ b> B on both sides of the light emitting panel 100 may have a planar plate shape. Alternatively, the first main surface 100A and the second main surface 100B may be non-planar.

  For example, as illustrated in FIG. 3, one of the first main surface 100A and the second main surface 100B may be curved. Alternatively, both the first main surface 100A and the second main surface 100B may be curved surfaces. The curved surface may be a convex curved surface as shown in FIG. 3 or a concave curved surface. Furthermore, one or both of the first main surface 100A and the second main surface 100B may be uneven.

  In this embodiment, the transmissive light emitting region 10 emits light from only one of the first main surface 100A and the second main surface 100B. For example, as illustrated by the arrow L1 in FIGS. 2 and 3, light is emitted from the first main surface 100A side, but light is not substantially emitted from the second main surface 100B side. Alternatively, conversely, light may not be emitted substantially from the first main surface 100A, and light may be emitted from the second main surface 100B.

  Furthermore, a part of the transmissive light emitting region 10 transmits light. For example, light can be transmitted from the first main surface 100A side to the second main surface 100B side as represented by an arrow L4 in FIGS. 2 and 3, and as represented by an arrow L3, The light can be transmitted from the second main surface 100B side to the first main surface 100A side.

  On the other hand, the peripheral region 20 is a region where, for example, electrode pads, drive circuits, and other various peripheral circuits and peripheral devices are appropriately provided. In this embodiment, the peripheral region 20 is not always essential and can be omitted as appropriate.

  In FIG. 1, although the substantially square thing was illustrated as the planar shape of the light emission panel 100, this embodiment is not limited to this. That is, the planar shape of the light emitting panel 100 can be a polygon, a circle, an ellipse, or various other shapes. Further, the planar shape of the transmissive light emitting region 10 is not limited to a substantially square shape as illustrated in FIG. 1, and may be a polygon, a circle, an ellipse, or various other shapes.

(First embodiment)
Next, a first embodiment of the light-emitting panel will be described with reference to FIGS. FIG. 4 is a conceptual diagram showing a planar configuration of a top emission type light emitting panel using an organic EL element as a light source. 5 is a cross-sectional view taken along line IIa-IIb in FIG. 6 is a cross-sectional view taken along line IIc-IId in FIG. 7 is a cross-sectional view taken along line IIe-IIf in FIG. FIG. 8 is an enlarged cross-sectional view of a part of FIG.

  In the light emitting panel 100, the transmissive light emitting region 10 includes a light transmitting portion 10a and a light emitting portion 10b. The transmissive light emitting region 10 includes portions where the light transmissive portions 10a and the light emitting portions 10b are alternately provided in a stripe shape. In the case of the specific example shown in FIG. 4, for example, when viewing the portion on the line IIe-IIf in FIG. 4 in FIG. 7, the light transmitting portions 10a and the light emitting portions 10b are alternately provided.

  The light emitting panel 100 includes a transparent first electrode layer 12, a reflective layer 13 as a light shielding layer, an organic EL layer 14 as a light emitting unit, and a transparent second electrode layer on a non-moisture transmissive substrate 11. 15 are stacked. Furthermore, it has a structure sealed with a moisture-impermeable protective cap 16. The reflective layer 13 is made of conductive aluminum. Accordingly, one surface of the reflective layer 13 and the first electrode layer 12 are electrically connected.

  As shown in FIGS. 4 and 7, the reflective layer 13 is disposed at a position corresponding to the light emitting portion 10b. One end in the longitudinal direction of the reflective layer 13 and the second electrode layer 15 are electrically insulated by the first insulating layer 171. The other end in the longitudinal direction of the reflective layer 13 and the second electrode layer 15 are electrically insulated by the second insulating layer 172.

  In the planar configuration shown in FIG. 4, a substantially rectangular region sandwiched between the first and second insulating layers 171 and 172 corresponds to the transmissive light emitting region 10, and is outside the first and second insulating layers 171 and 172. The region corresponds to the peripheral region 20 (see FIG. 1).

  As shown in FIGS. 6 to 8, a transparent resin layer (insulating light transmission layer) 18 is provided in a space formed between the first electrode layer 12 and the organic EL layer 14 on the side surface of the reflective layer 13. Filled. Resin layers (insulating light transmission layers) 18 are provided and filled on the side surfaces of the reflective layers 13 located at both ends in the arrangement direction up to the side surfaces of the translucent substrate 11. The resin layer (insulating light transmission layer) 18 can be formed by filling and curing transparent polyimide, for example.

  As shown in FIG. 7, an insulating layer 18 is interposed between the first electrode layer 12 and the second electrode layer 15 on both sides in the arrangement direction of the plurality of reflective layers 13. The insulating layer 18 in this portion performs the same insulating action as the first and second insulating layers 171 and 172 formed at both ends in the longitudinal direction of the reflective layer 13 shown in FIG. For this reason, the insulating layer 18 can also be used to form insulating layers corresponding to the first and second insulating layers 171 and 172.

  The first electrode layer 12 is formed by depositing, for example, ITO (Indium Tin Oxide) with a thickness of 150 nm. The first electrode layer 12 can also be formed of tin oxide, indium and tin oxide, or the like. The first electrode layer 12 is disposed to the outside of the protective cap 16 and serves as one first electrode pad 191 to which power is supplied.

  The second electrode layer 15 laminated on the organic EL layer 14 has one end on the top surface of the first insulating layer 171 and the other end on the top surface and side surfaces of the second insulating layer 172 and along the translucent substrate 11. It is arranged to the outside of. The second electrode layer 15 disposed outside the protective cap 16 serves as the other second electrode pad 192 to which power is supplied.

  The first and second electrode pads 191 and 192 can be provided with electrodes for power supply on the common side of the light emitting panel 100 by drawing one of them to the other side. In this case, wiring routing can be reduced.

  The translucent substrate 11 can be formed of various materials such as glass, quartz, plastic, and resins. Further, the light-transmitting substrate 11 is not required to have zero light transmittance, and may be colorless and transparent, colored and transparent, translucent, or opaque.

  The light emitting unit is not limited to the organic EL layer 14 and may be, for example, an LED (Light Emitting Diode) or an LD (Laser Diode).

  According to the configuration shown in FIG. 7, when the first electrode pad 191 and the second electrode pad 192 are supplied with power, the organic EL layer 14 can emit light. As shown in FIG. 5, the power supplied to the first electrode pad 191 is supplied to one surface of the organic EL layer 14 via the first electrode layer 12 and the reflective layer 13. The power supplied to the second electrode pad 192 is supplied to the other surface of the organic EL layer 14 via the second electrode layer 15. As a result, the organic EL layer 14 positioned on the reflective layer 13 and the second electrode layer 15 can emit light, and light can be emitted 360 degrees around the light emitting portion. The organic EL layer 14 that emits light corresponds to the light emitting portion 10b.

  Then, as shown in FIG. 7, the light emitted from the organic EL layer 14 and traveling toward the first main surface 100 </ b> A of the light-emitting panel is emitted from the first main surface 100 </ b> A. On the other hand, the light emitted from the organic EL layer 14 and traveling toward the second main surface 100B side of the light emitting panel is provided with a reflective layer 13 that is a light shielding layer. For this reason, the light emitted from the organic EL layer 14 is not emitted in the direction of the arrow L2. The light L1a directed in the direction of the arrow L2 is reflected by the reflective layer 13 and is combined in the directions of the arrows L1 and L1a to play a role of improving illuminance.

  On the other hand, the reflection layer 13 is not provided in the light transmission part 10a. Therefore, as shown in FIGS. 6 and 7, light is transmitted in the direction of the arrow L3 through the translucent substrate 11, the first electrode layer 12, the resin layer 18, the organic EL layer 14, and the second electrode layer 15. It is possible. Also, light can be transmitted in the direction of the arrow L4 opposite to the arrow L3.

  This embodiment is not limited to the specific examples shown in FIGS. For example, the light emitting portions 10b (or the light transmissive portions 10a) are not limited to those formed in stripes and alternately arranged, and may be in a matrix shape with equal pitches in the vertical and horizontal directions. It may be a staggered pattern or various non-periodic arrangement patterns.

  Further, the planar shape and the planar size of the plurality of light emitting portions 10b (or the light transmitting portions 10a) are not necessarily the same, and may include the light emitting portions 10b having different planar shapes and planar sizes.

  Further, the ratio of the area of the light transmitting portion 10a and the light emitting portion 10b is not limited to that illustrated in FIGS. If the area ratio of the light transmission part 10a is increased, the amount of light transmitted through the light emitting panel 100 can be increased. On the contrary, if the ratio of the area of the light emitting portion 10b is increased, the amount of light emitted from the light emitting panel 100 can be increased. Therefore, the ratio of these areas can be appropriately adjusted according to the use of the light-emitting panel 100, required specifications, performance, and the like.

  Since the conductive reflective layer 13 is formed on the first electrode layer 12 in this way, power can be supplied from the first electrode layer 12 even when the reflective layer 13 is an independent pattern, and lighting in an arbitrary pattern is possible. Is possible. Further, the side surface of the reflective layer 13 is filled with the resin layer 18 so that the upper surface of the reflective layer 13 and the upper surface of the resin layer 18 can be flush with each other.

  Thus, the second electrode layer 15 can be formed by a method of forming a film on the reflective layer 13 and the resin layer 18 by spin coating and leaving a necessary portion by a photolithography method using a mask.

  Similarly, the resin layer 18 is filled by using a spin coat method to form a film including the space between the reflective layers 13 on which the polyimide is arranged, and patterning the polyimide film by a photolithography method so that the light transmitting portion 10a remains. did.

  In this embodiment, a light-emitting panel having a configuration in which a part other than the reflective layer out of the configuration up to the second electrode layer can be formed by spin coating and a necessary portion can be left by photolithography using a mask is realized. Can do.

  Here, the manufacturing method of the light emitting panel 100 described in the first embodiment will be described in further detail.

  A soda-lime glass substrate (vertical and horizontal 100 mm × 100 mm, thickness = 0.7 mm) was used as the non-moisture transmissive substrate 11. An ITO film having a thickness of 150 nm was formed on the surface of the light-transmitting substrate 11 by sputtering as the first electrode layer 12.

  Subsequently, a reflective film was formed as the reflective layer 13 on the first electrode layer 12 using a vacuum deposition method.

  Here, in order to determine the transmittance of the transmissive light emitting region 10, for example, when a light emitting panel having an area ratio of the light transmissive portion 10a of 85% is created, the total area of the mask portions is the total area of the mask of the vapor deposition mask. The light shielding layer 32 was formed using vapor deposition masks arranged at regular intervals and periodically so as to be 15%. As the reflective layer 13, an Al (aluminum) film having a thickness of 400 nm was formed.

  The reflective layer 13 can also be formed by a method of thermal transfer from the aluminum donor sheets arranged in the array shown in FIG.

  Next, first and second insulating layers 171 and 172 are formed for the purpose of preventing poor contact between the ITO film as the first electrode layer 12 and the ITO film as the second electrode layer 15 in a later step. The first and second insulating layers 171 and 172 are realized by forming a polyimide film with a thickness of about 1.5 μm using a spin coating method. The first and second insulating layers 171 and 172 were processed into a shape sandwiching them at both ends in the longitudinal direction of the light transmitting portion 10a and the light emitting portion 10b.

  Next, the organic EL layer 14 that emits two-wavelength white light is formed on the ITO film by vacuum evaporation. As the organic EL layer 14, first, α-NPD is deposited to a thickness of 60 nm as a hole transport layer. Subsequently, as a blue light-emitting layer, α-NPD (diphenylnaphthyldiamine) is used as the host material, perylene is used as the dopant material, and a 20 nm thick film is formed so that the dopant concentration is 1 wt%. Next, as a red light emitting layer, Alq3 [tris (8-quinolinolato) aluminum] is used as the host material, DCM1 is used as the dopant material, and a 40 nm thick film is formed so that the dopant concentration is 1 wt%. Finally, Alq3 is deposited to a thickness of 20 nm as an electron transport layer.

  Subsequently, ITO was formed as the second electrode layer 15 with a thickness of 150 nm by using a photolithography method.

  The organic EL element produced in this way is very fragile to moisture in the outside air. Therefore, the organic EL layer 14 was hermetically sealed with a non-moisture permeable protective cap 16. In this embodiment, since light transmission is required in the light transmission part 10a, the moisture-impermeable protective cap 16 also has light transmission.

  A soda-lime glass substrate was used as the moisture-impermeable protective cap 16. As an airtight sealing method, a UV curable adhesive is applied to the edge of the soda lime glass substrate, and the protective cap 16 is bonded so as to cover the transmissive light emitting region 10. Then, UV is irradiated to an adhesive application part in the state which shielded light so that UV may not be irradiated to the organic electroluminescent layer 14, an adhesive agent is hardened, and it joins airtightly.

  In this method for manufacturing a light-emitting panel, a resin layer is filled in a space without a reflective layer sandwiched between first and second electrode layers. For this reason, when the second electrode layer is formed, a film can be formed by spin coating, and a necessary portion can be left by a photolithography method using a mask. This is because the same photolithography process as that for forming the first electrode layer can be used, and a common manufacturing system can be realized.

(Second Embodiment)
With reference to FIG. 9 and FIG. 10, a second embodiment relating to the light-emitting panel will be described. FIG. 9 is a conceptual diagram showing a planar configuration. FIG. 10 is an enlarged cross-sectional view of a part of FIG.

  The thickness of the organic EL layer 14 is about 150 μm at most. For this reason, there is a possibility that the second electrode layer 15 hangs down near the boundary between the reflective layer 13 and the resin layer 18. In this case, the second electrode layer 15 and the conductive reflective layer 13 may be short-circuited. In this embodiment, a short circuit between the second electrode layer 15 and the reflective layer 13 is prevented.

  That is, as shown in FIG. 10, a gap X was formed between the upper surface of the reflective layer 13 and the upper surface of the resin layer 18. The gap X is obtained by subtracting the thickness C of the resin layer 18 from the thickness B of the reflective layer 13 (X = B−C). The relationship between the gap X and the thickness A of the organic EL layer 14 is X <A.

  When the gap X and the thickness A of the organic EL layer 14 satisfy the relationship X <A, a sufficient distance is secured so that the reflective layer 13 and the second electrode layer 15 do not short-circuit even when the second electrode layer 15 hangs down. be able to. For this reason, the malfunction of the non-lighting of the organic EL layer 14 in the short-circuited portion can be prevented.

  In this embodiment, the short-circuit with the reflective layer due to the sagging of the second electrode layer is prevented, thereby contributing to prevention of non-lighting of the organic EL layer.

(Third embodiment)
With reference to FIGS. 11 and 12, a third embodiment relating to a light-emitting panel will be described. FIG. 11 is a conceptual diagram showing a planar configuration. 12 is an enlarged cross-sectional view of a part of FIG. In this embodiment, as in the second embodiment, a short circuit between the second electrode layer 15 and the reflective layer 13 is prevented.

  In this embodiment, as shown in FIG. 12, the height of the upper surface of the insulating layer 18 is formed higher than the upper surface of the reflective layer 13 by Y.

  Since the insulating layer 18 is higher than the reflective layer 13, the second electrode layer 15 is prevented from sagging. In addition, the distance between the second electrode layer 15 and the reflective layer 13 is widened, which contributes to prevention of these short circuits.

  In this embodiment, the second electrode layer is prevented from sagging and a short circuit with the reflective layer is prevented, thereby contributing to prevention of non-lighting of the organic EL layer.

  The present invention is not limited to the above-described embodiment. For example, when a plurality of light emitting portions 10b are interspersed in the light transmitting portion 10a, each light emitting portion 10b may be individually turned on. This can be realized by using a switching element such as a TFT (Thin Film Transistor). In this way, only a part of the transmissive light emitting area 10 can be turned on, and characters, figures, image data, etc. can be displayed.

  Further, for example, a light emitting unit 10b that emits red (R), a light emitting unit 10b that emits green (G), and a light emitting unit 10b that emits blue (B) are arranged adjacent to each other. It is also possible to form a pixel and periodically arrange the pixel in the transmissive light emitting region 10. In this case, color display is also possible by controlling the emission intensity of red, green and blue of each pixel.

  The above-described transmissive light emitting panel is very useful in the development of organic EL lighting in the in-vehicle field, the housing field, the advertising field, and the like. For example, when the transmissive light emitting panel of this embodiment is used as a head-up display in an automobile window, external light can be taken in through the light emitting panel.

  In addition, when it is desired to brighten the interior of the vehicle, the lighting panel can be turned on to function as illumination. As a result, energy can be saved by making good use of outside light, and since it is integrated with the window, it can have an advantage that cannot be imitated by other in-vehicle light sources in terms of design and space.

  Although several embodiments have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, combinations, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 100 Light emission panel 100A 1st main surface 100B 2nd main surface 10 Transmission light emission area | region 20 Peripheral area | region 10a Light transmission part 10b Light emission part 11 Translucent board | substrate 12 1st electrode layer 13 Reflective layer 14 Organic EL layer 15 2nd electrode layer 16 Protective cap 171 First insulating layer 172 Second insulating layer 18 Resin layer 191 First electrode pad 192 Second electrode pad

Claims (7)

A light-emitting panel having a transmissive light-emitting region that emits light and transmits light,
The transmissive light emitting region has a light emitting part that emits light and a light transmissive part that transmits light,
The light emitting portion includes a light emitting portion that emits light, and a conductive reflective layer that blocks and reflects light.
The light emitting unit includes a conductive and translucent first electrode layer electrically connected to one surface of the reflective layer, and a conductive and translucent second electrode disposed to face the first electrode layer. A layer, and an organic EL layer interposed between the second electrode layer and the first electrode layer,
The light transmission portion includes the first electrode layer where the reflective layer is not located, the second electrode layer, and the organic EL layer,
A light emitting panel comprising: a resin layer (insulating light transmitting layer) filled in a space between the first electrode layer and the organic EL layer of the light transmitting portion.   Light traveling from the light emitting unit toward the first main surface of the light emitting panel is emitted from the first main surface, and light traveling from the light emitting unit toward the second main surface of the light emitting panel is reflected from the reflective layer. The light-emitting panel according to claim 1, wherein the light-emitting panel is shielded by.   The light emitting panel according to claim 1, wherein the organic EL layer has a top emission type light emitting structure.   The light emitting panel according to claim 1, wherein a height of an upper surface of the reflective layer is lower than an upper surface of the resin layer (insulating light transmission layer).   The light emitting panel according to any one of claims 1 to 3, wherein a height of an upper surface of the reflective layer is higher than an upper surface of the resin layer (insulating light transmitting layer). A method of manufacturing a light-emitting panel having a light-emitting region that emits light and transmits light,
A light-transmitting and conductive first electrode layer is formed on the surface of the moisture-impermeable light-transmitting substrate,
Forming a conductive reflective layer on the first electrode layer;
Forming an organic EL layer on the reflective layer;
Forming a translucent and conductive second electrode layer on the organic EL layer;
Filling the resin between the first electrode layer other than the reflective layer and the organic EL layer to form a resin layer (insulating light transmission layer),
A method for manufacturing a light-emitting panel, except that the reflective layer is formed by spin coating, and necessary portions are formed by photolithography using a mask.   The light emitting panel manufacturing method according to claim 6, wherein the reflective layer is formed by a sputtering method or a thermal transfer method.

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